1. Field of the Invention
This invention relates to mixed-solid solution tri-metallic oxide/sulfide catalysts useful for hydroforming reactions. The active metallic catalyst is in oxide or sulfide form and mixed with a solid solution substrate of at least two metallic oxides. The catalysts are stable and active under high temperature conditions and are tolerant to sulfur containing feed materials.
2. Description of the Prior Art
Specific metal oxides and metal sulfides and mixtures of metal oxides and metal sulfides are known to serve as catalysts, particularly for low temperature hydrogenation reactions. U.S. Pat. No. 3,116,345 teaches a catalyst for hydroisomerization which is a sulfide of one or more metals of chromium, molybdenum, and tungsten and/or a sulfide of one or more metals of iron, cobalt and nickel on a solid support of silica, alumina, or mixed silica-zirconia. U.S. Pat. Nos. 4,151,191 and 4,260,553 teach mixed metallic catalysts of molybdenum oxides or sulfides, lanthanide and actinide oxides or sulfides; and aluminum, tungsten and silicon oxides may be used as methanation catalysts up to about 600.degree. C. U.S. Pat. Nos. 4,320,030 and 4,491,639 teach vanadium, molybdenum or tungsten sulfide or mixed sulfide/oxide compounds which may contain aluminum, silicon, boron, cerium or titanium; cobalt, nickel, iron or manganese; carbon; and nitrogen for use as hydrogenation catalysts. The applicants do not have knowledge of any tri-metallic oxide/sulfide catalysts wherein a first metallic oxide/sulfide is mixed with a solid solution of a second and third metallic oxide material.
Conventional technologies of conversion of liquids derived from naturally carbonaceous sources to light-medium hydrocarbons are catalytic processes of hydro-treating, hydro-cracking, and steam reforming. In steam reforming, sulfur compounds deactivate and phenolic compounds increase fouling of the catalyst. Therefore, the feedstock must be processed to remove acid gases prior to steam reforming. Feedstock having an end point higher than that of naphtha, about 365.degree. F., cannot be commercially reformed at the present time. The requirement of high temperature, high pressures, hydrogen and steam as reactants in the conventional processes result in high costs. For example, in a conventional coal or oil conversion process, the effluent stream from the conversion reactor is conventionally quenched to about 95.degree. to 130.degree. F. to remove naphthas, oils, fatty acids, phenols and tars and process steam is condensed and treated before disposal. The cooled material is then fed to a hydro-treating/hydro-cracking reactor which is operated under pressurized conditions of up to 2,000 psig and heated to temperatures in the order of 700.degree. to 800.degree. F. and the reaction consumes large quantities of fresh hydrogen. Sulfur must be removed from the product stream of the hydro-treating/hydro-cracking vessel to a low concentration, in the order of 0.1 to 0.5 ppm, to insure that the steam reforming catalyst is not poisoned. In the following steam reformer/hydroformer, fresh steam is required and the hydrocarbon feed is limited to endpoints below 365.degree. F.
Exemplary of recent prior art relating to conversion of naturally occurring carbonaceous materials and its hydroconversion are U.S. Pat. Nos. 4,582,630; 4,594,140; 4,613,584; 4,620,940; 4,624,684; 4,654,164; 4,678,480; 4,678,600; 4,681,701; 4,690,690; and 4,690,814.